Heytools - JavaScript tools, AJAX tools and some fully server side tools.
WordCounter.net - Count words, sentences, paragraphs etc.
NimbleText - NimbleText is a text manipulation and code generation tool available online or as a free download.
Word Count Tools - The must-have free word counter that provides an extensive report about the word count, character count, keyword density, readability & many other useful stats.
ThinkCalculator - Online Calculator Resources
KeywordDensityAnalyzer.com - Website Keyword Density Analyzer Tool